The boys resumed their walk, talking on topics of interest to them and keeping their eyes "peeled," as Adrian expressed it, for old bones, that they might know where to locate them when they came another day. They had gone about two miles, rambling slowly along, when, as they turned a bend in the road, they caught sight of two men carrying valises, hurrying on, just ahead of them. "They look like book agents," ventured Adrian. Roger glanced sharply at the receding figures. "Why," he exclaimed, "they are the two men who are boarding at Crownheart's hotel, the ones who came in on the stage the other night. I guess they must be looking over the ground for the new railroad." "Let's chase after them and see what they do," suggested Adrian, and then the boys, having some object in their walk, quickened their pace to catch up to Mr. Dudley and Mr. Ranquist. In a few minutes the men reached an open field on the left side of the road,--a pasture filled with big stones and bowlders that had fallen from a great ledge of rock two hundred feet high or more, which cropped out about seven hundred feet from the highway, and rose, almost abruptly, from the level of the field. "Hold on a minute," cautioned Adrian, as he saw the men stop. "Don't let them catch us playing 'I spy'; they might not want us to follow them, even though we have a right to go where we please. We'll just wait by the tree until we see which way they turn." The boys sat down in the shade of a big maple. "What's that queer smell," asked Roger suddenly, sniffing the air. "Sulphur spring," explained Adrian. "This is what they call 'Stony Farm.' Belongs to Jim Eaton, and about all it's good for is to pasture sheep. The sulphur spring comes out of that rocky ledge and runs across under the road. Some folks say the water's healthy, but it tastes too much like rotten eggs for me. The cattle won't drink it. But say, those men are going in," and he rose to peer at them. Mr. Dudley could be seen pointing toward the big rocky hill, and he appeared to be urging his companion to advance toward it. The younger man seemed to be in favor of going farther on before turning off the road, and he indicated a place about half a mile distant. But in the end the older man prevailed, and the two, after a cautious glance on all sides, struck into the field and made their way to a path that led up on top of the out-cropping rock. After waiting until the men had well advanced, Roger and Adrian took after them. Proceeding slowly along, the boys saw the men ascend to the top of the big ledge, and then turn to the left, going back in the direction they had come from. On top of the rocks was a sort of path, made by the sheep and cows that used it to pass into the woods during hot days. The men walked along this, for perhaps a mile, stopping every now and then to examine the ground closely. Once in a while the younger man would chip off a bit of rock, which he and his companion would look at carefully.